Method of and apparatus for determining deviation in drilling wells



Sept; 12,1933. 1.. BURRELL ET AL METHOD OF AND APPARATUS FOR DETERMININGDEVIATION IN DRILLING WELLS Filed Dec. 26, 1929 5 2 2 5/ a 2 4 EH 4 5 5Patented Sept. 12, 1933 METHOD ',OF .AND APPARATUS: Foa DE-Q'I TERMININGWELLS} DEVIATKON'" IN -DRILI1ING;

Logan Burrell and Henry West, Los Angeles, I

Calii., assignors, to Shell' 0il Qompany, San, Francisco; Calif., acorporation of- California Application December 2.6, 1929. l

- Serial lNo. 416,543 1 I this; deviation, these devices usually,employing a means for determining the inclination to the vertical. of 'aparticular portion of the" hole so that by calculation it is possible todet'erminethe amount of "deviation'i Such devices are often complicatedto usefandc have the disadvantage that the deviation is'notgivendirectly, but'must 1 be calculated.-

.It is an object of, our, inventioutoprovide a nieth'odz ofdeterminingthe deviation of a well in which the deviation, may 'bfemeasured directly from the projection of the well onthe surface of theg'roundlf' termining Ltheprojection of the'well on the surface of theground, whiclilmethodfconsistsj in -de termining the projected;positionson the surface of the ground of apluralityof points in the welland determining a-line through the points t0de termine' the projectionof the well.

V A further object is topro'videaf method' jof 10;; eating from thesuriace'of, the ground thepro- 1 M 5 jected positions" or the points inthe well. 1

it is also an object to provide a methodof locating a point-in a wellfrom'apoint at thesurface of the ground, which method consistsfintrans;n itting a wavemotion between the points, the direction-of thewave motion betweemthe points indicatingthe, direction of the pointsrelativeto each other.v I r a v H Another object is to provide a methodof the aboveclassin which a waveis transmitted from a 'point in the:well: and is received; at aa plurality of stations-atthe surface, theintersection. of the various directions from which the wave motion wasreceived {at the stations beingdetermined iniorderto locate the point.

A further object is to providea" method of the above class inwhich radiowaves are transmitted by a transmitter.

Another object is to provide suitable apparatus for accomplishing theabove'rnethodsl Anotherobject is to provide a, method of, de-

6 i clai s, (01. 250-11 1 In the drawing,. p V

Figgl'is aplan vie-w of5 the surface ofthe ground. above a well showinga preferred methodoflac; complishing= our invention.- i Fig.- 2 isa-sectional view. taken; well. A Referring to the drawing, wet-shows3;,WG11I11" through. the

" whichhas been dug by a bitsecured to the lower end ofa-drill pipe12'c0ntro1led1froma derrick 13:

at the surface of the ground. Dueto, the drill pipe 12 beingdefiected atanumber of points, the well; 11 has been-dug, crookedand has deviatedfrom-the-vertical; as showniin-Fig. 2.

In -order to-determine theamount of suchdee viation; we providearadiotransmitter 20; which may be-of; any welt-known type, operable totransmit radio waves therefrom. In the preferred form or" our invention,the radio transmitter 20 is secured tothe' lower end ofithe-drill pipe12 r and is lowered thereby-to apoint 22in the well 11'. Operationof'the transmitter 20 isithenistarted and 'radiowaves' aretransmitted-thereby, the radio waves passing through the ground alldirections and outward intothe space above the ground; as is wel-l'known. The radio -.waves trans? mitted' by-he transmitter 20. arereceived by a receiver 24 which-isl'ocated at a point .25 at the surfaceof the; ground; the radio waves passing betweerithe points 22 and 25along a direction mine the direction of: the point -22 relative to thepoint'2fig'i-tis only necessarytodetermine the 7, Further objects of ourinvention wi1l5bernade V evidentin the ensuing description.

d irectionline 28 along which theradio waves'pass between-thepoints22and 25" This may be de-' terminedby' providing a dire'ctionaldetermining device on thereceiver 24 for determining the directionfromwhich the-radio waves sent. out: by 20' are-received. Inthepreferred form of our in- ,vention," however, we prefer t0= determineonly the projectionparallel 'tothe surfaceof the "ground of -the line28; Which projection" isihor-izontalin the case shown; This isdetermined. by making the directional:determiningdeviceonithetransmitter 20 aloop aerial 30 which islmounted for-rotation aboutave'rtical axis. The1o0p=aerial 30 is rotated'until'the signals asreceivedzby the receiver 24 from 'thetransmitter 20 are loudest at whichtime the planeof theloop aerial3.30 coincideswith a vertical plane'passing through thepoints 22 and 25." A line 32=parallelrtothe surfaceof the ground maythen. be determined "by the' direction of the loopaerial; which; line 32 lies in the vertical plane passing through thepoints 22and 25 and is the projection of the line 28 on the surface of,the ground. 7 p

The receiver 24 is then moved'to a point34 and the operation'isrepeatedto determine a line 35 which is the-projection on the surface of theground of a line 36 along which radio waves transmitted by thetransmitter 20 pass between the points 22 and 34. The intersectionoflines '32 and 35 is a point 40 whichis'the projected po,-,

sition of the point 22 on the surface of the ground. We prefer to repeatthe above operation at a third point42 on the surface of the ground-Having determined the projection of the point,

22 on the surface of the ground to be point 40,

' we then lower thedrill pipe 12 so as to move the transmitter 20 to apoint 46 in the well and repeat the above operationtodeterminetheprojected position of the point 46,,on the surface of the ground,this being found to be a point 47. The transmitter 20 isthen lowered toappoint 50 which may beat the bottom of the well 1'1,-and

the projected position ofthe point 50 obtained in a like manner, point52 being thus determined to be the projection of the point 50.Theproj'ecte'd positions-of other points, may be deteri mined in alikemanner, if desired. A line 54 passing through .the, derrickjl3. and the-points 40, 47 and 52 is then determined graphically by other-means, theline 54 being the projectionof the well 11 on the surface of the ground.Having determinedthe projection of the wellfll, the de viation betweenany';two points may bereadily obtained by measurement. j r t It shouldbe noted, that, they above method V wasbased on thesassumption that thetransmitterf20 was located at a point in the well 11 and that'thereceiver 24 was located at a point on thesurface of the ground, Itshouldbe understood thatweare not limited to this arrangement, as thereceiver 24' may be positioned at points in the well '11 and thetransmitter 20 may be positioned at points on the surface ,of theground, if desired. When the receiver 24 and the transmitter 20 are sopositioned, thedrillpipe 12 ;is.rotated in order tor'otate-thetransmitter 20 and they directionaldetermining device secured thereto sothat the signals as received by the transmitter 20 when located at oneof the points, suchas 25, are loudest, thedirectional determin n deviceof 'the transmitter 20 being then in a position to indicate the,directionof the point 25 from-the point 22; this. being the line 32,asalready explained. The transmitter 20 is then moved to the otherpoints. 34 and 42 and the directions of the lines 35 and 43 determinedin a like manner.

[.'It shouldbe understood, however, that the tr'ansmitter'rZO maybeequipped withv the direcltional transmitting apparatus, this apparatusbe-- iing of, atype, which is well known in the radio art and whichtransmits radio waves in one direction from the transmitter 20. Whensuch is the case, the directional transmitting apparatus of'thetransmitter 20 is rotated until the signals are received by the receiver24, The direction of the directional trans1nitting' apparatus 'on' thetransmitter 20then indicates the direction of the receiver 24 from thetransmitter 20. It will thus case the loop aerial 30 is turned so thatit rotates tion of a "well on the surface of the ground, which includesthe steps of: transmitting a wave mobe seen that the location of a pointin the'well relative to a point on the surface of the ground isdetermined bytransmitting a wave motion betweenthe point in the well andthe'p'oint on the surface of the ground and determining thedirectionalong which the wave motion passes between the points as anindication of the direction of the points relative to each other.

It should also benoted that only one point on the surface ofthe groundis required to give the direction of a pointin the well from the pointon the surface of the ground, and that only two points on the surface ofthe ground are required to give a complete location of any point'in thewell, since the intersection of two of the, direction lines 32,35 or 43will be a point.

However, as stated above, we prefer to use three or more stations, aseach station :used gives a more definite determination of the projectedposition of the point in the well.

It is within the scope of our invention to use the deviation determiningapparatus during the time that the drill bit isdrilling the well, suchan arrangement making it possible to determine thedeviation as thewell'is dug. I

Our invention may also be used to determine the depth of a point, suchas point 22, in the well by the method shown in Fig. 2. In this about ahorizontal axis and isoperable'toindicate the. vertical direction of thepoint 22 relative to a point on the surface, such as the point 25thisbeing determined tobe the line 28 as will. be readily apparent.Direction lines may be taken from two or more stations on the surface ofthe ground and the intersection of such lines gives the verticalposition of the point 22 relative to the points on the'surface of theground and thus gives the depth of the point 22 below the surface of theground. I I

Although. we have described and claimed the radio transmitter 20, astransmitting radio waves, it'should bejunderstood that we are onlyproviding an explanation of the operation in ac- .7 cordance withanaccepted theory of the radio method of transmitting energy between twoceivedmay be determined; Furthermore, it is conceivablethat other typesof wave motion may be employed for this purpose without departing fromthe spirit of our invention.

We claim as our invention: u

1 3A method of determining the deviation during' the drilling of a well,which includes the steps of: transmitting a wave motion from a pointwithin the well, said point being near the bottom of the well; receivingsaid wave motion at-a plurality of points'on the surface of the ground;determining the directions between the transmitting and receivingpoints; determining the intersection of said directions as an indicationof the position of thetransmitting pointjand determining the verticalprojection of said intersection on-thesurface of the ground as anindication of the deviation of the well.

2. A method of determining the vertical projection between a point insaid well and a plurality of points on the surface of theground;fdetermining the directions between said point in mi; well andthe points on the surface of the ground;

determining the intersection of said directions; and determining thevertical projection of said. intersection on the surface of the ground;and

repeating the same method for determining vertical projections of otherpoints along the bore of the well, as indications of the outline of thevertical projection of the well on the surface of the ground; r

3. The method of determining the outline of a borehole comprising thesteps: transmitting radio signals from a point within the borehole;receiving said signals at two or more points on the surface of theground; determining the I straight line directions between thetransmitting and receiving points; determining the intersection point ofsaid directions, as an indication of the true position of thetransmitting point; and repeating the same steps for locating one ormore vadditional points along the borehole, as indications of theborehole outline.

4, A method of'determining the plan View of a Well comprising the steps:vtransmitting a wave motion from a point in the well to at least tworeceiving points on the surface of the ground;

the operations of transmitting and receiving of the radio'signals, andregistering of the direc-' tions between the transmitting and receiving7 points is carried on while the well is being drilled. 6. The methodfor determining the deviation of a borehole from a vertical through itstop comprising the steps: transmitting radio signals from a point in theborehole; receiving said signals at two or more points on the surface ofthe ground; determining vertical plane directions through thetransmitting and receiving points; determining the intersection line ofsaid directions and its vertical projection on the surface, as anindication of said deviation.

- LOGAN BURRELL.

HENRY WEST.

